1 /***
2 * Redistribution and use of this software and associated documentation
3 * ("Software"), with or without modification, are permitted provided
4 * that the following conditions are met:
5 *
6 * 1. Redistributions of source code must retain copyright
7 * statements and notices. Redistributions must also contain a
8 * copy of this document.
9 *
10 * 2. Redistributions in binary form must reproduce the
11 * above copyright notice, this list of conditions and the
12 * following disclaimer in the documentation and/or other
13 * materials provided with the distribution.
14 *
15 * 3. The name "Exolab" must not be used to endorse or promote
16 * products derived from this Software without prior written
17 * permission of Exoffice Technologies. For written permission,
18 * please contact info@exolab.org.
19 *
20 * 4. Products derived from this Software may not be called "Exolab"
21 * nor may "Exolab" appear in their names without prior written
22 * permission of Exoffice Technologies. Exolab is a registered
23 * trademark of Exoffice Technologies.
24 *
25 * 5. Due credit should be given to the Exolab Project
26 * (http://www.exolab.org/).
27 *
28 * THIS SOFTWARE IS PROVIDED BY EXOFFICE TECHNOLOGIES AND CONTRIBUTORS
29 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
30 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
31 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
32 * EXOFFICE TECHNOLOGIES OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
33 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
34 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
35 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
37 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
39 * OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Copyright 2000-2001,2003 (C) Exoffice Technologies Inc. All Rights Reserved.
42 */
43
44 package org.exolab.jms.selector;
45
46 import javax.jms.Message;
47
48
49 /***
50 * This class implements a 'between' expression.
51 * This is a boolean expression of the form:
52 * numeric-expr1 between numeric-expr2 and numeric-expr3
53 * This is equivalent to:
54 * numeric-expr1 >= numeric-expr2 and numeric-expr1 <= numeric-expr3
55 *
56 * @version $Revision: 1.1 $ $Date: 2004/11/26 01:50:44 $
57 * @author <a href="mailto:tma@netspace.net.au">Tim Anderson</a>
58 * @see Expression
59 * @see SBool
60 */
61 class BetweenExpression implements Expression {
62
63 /***
64 * Corresponds to numeric-expr1
65 */
66 private final Expression _num1;
67
68 /***
69 * Corresponds to numeric-expr2
70 */
71 private final Expression _num2;
72
73 /***
74 * Corresponds to numeric-expr3
75 */
76 private final Expression _num3;
77
78 /***
79 * The expression context, for error reporting purposes
80 */
81 private static final String CONTEXT = "between expression";
82
83
84 /***
85 * Construct an expression that returns num1 >= num2 and num1 <= num3
86 * when evaluated
87 *
88 * @param num1 arithmetic expression
89 * @param num2 arithmetic expression representing the
90 * lower bound
91 * @param num3 arithmetic expression representing the
92 * upper bound
93 */
94 public BetweenExpression(final Expression num1, final Expression num2,
95 final Expression num3) {
96 _num1 = num1;
97 _num2 = num2;
98 _num3 = num3;
99 }
100
101 /***
102 * Evaluate the 'between' expression
103 *
104 * @param msg the message to evalulate the expression against
105 * @return an SBool instance
106 * @throws TypeMismatchException if any of the expressions are not numeric
107 */
108 public final SObject evaluate(final Message msg)
109 throws TypeMismatchException {
110 SBool result = null;
111 SNumber val1 = TypeCaster.castToNumber(_num1.evaluate(msg), CONTEXT);
112 if (val1 != null) {
113 SNumber val2 = TypeCaster.castToNumber(_num2.evaluate(msg),
114 CONTEXT);
115 if (val2 != null) {
116 SNumber val3 = TypeCaster.castToNumber(_num3.evaluate(msg),
117 CONTEXT);
118 if (val3 != null) {
119 if (val1.greaterEqual(val2).value()
120 && val1.lessEqual(val3).value()) {
121 result = SBool.TRUE;
122 } else {
123 result = SBool.FALSE;
124 }
125 }
126 }
127 }
128 return result;
129 }
130
131 /***
132 * Return a string representation of this expression
133 *
134 * @return a string representation of this expression
135 */
136 public final String toString() {
137 StringBuffer result = new StringBuffer();
138 result.append('(');
139 result.append(_num1.toString());
140 result.append(" between ");
141 result.append(_num2.toString());
142 result.append(" and ");
143 result.append(_num3.toString());
144 result.append(')');
145 return result.toString();
146 }
147
148 }